Preparation of monocyclopentadienyl metal complexes by nucleophilic substitution of bis(cyclopentadienyl) metal complexes

ABSTRACT

Bridged monocyclopentadienyl derivatives of a Group 4 metal are prepared by contacting a corresponding bis(cyclopentadienyl) metal complex with an alkali metal derivative or alkaline earth metal derivative of a hydrocarbyl ligand R, which is optionally substituted with one or more amino, phosphino, ether, thioether, or silyl groups. The bis(cyclopentadienyl) Group 4 metal complexes can be prepared by contacting a compound corresponding to one of the formulas (Cp) 3  MQ n  X t , (Cp) 2  MQ n  X t+1 , or CpMQ n  X t+2  and a dianionic salt compound corresponding to the formula: (L +x ) y  (Cp*-Z-Y) -2  or ((LX&#39;) +x ) y  (Cp*-Z-Y) -2 . An addition polymerization catalyst comprising a bis(cyclopentadienyl) Group 4 metal complex and an activating cocatalyst, and an addition polymerization process using such a catalyst.

BACKGROUND OF THE INVENTION

This invention relates to a process for preparing certain bridgedmonocyclopentadienyl Group 4 metal complexes. More particularly, thisinvention relates to such a process involving nucleophilic substitutionof corresponding bis(cyclopentadienyl) Group 4 metal complexes. Further,the invention relates to bis(cyclopentadienyl) Group 4 metal complexes,to a process for preparing the same, and to an addition polymerizationprocess using a catalyst comprising the same complex and an activatingcocatalyst.

Monocyclopentadienyl Group 4 metal complexes, particularly those whereinthe cyclopentadienyl derivative group is part of a bridging ligand groupare known and useful in catalyst compositions for additionpolymerizations, particularly in polymerizing and interpolymerizingolefins, diolefins, vinyl-aromatic monomers, and/or acetylenicallyunsaturated monomers.

Bridged monocyclopentadienyl Group 4 metal complexes, including thosewhich also contain at least one hydrocarbon group other than acyclopentadienyl covalently bonded to the Group 4 metal, are disclosedin EP-A-0,416,815, EP-A-0,418,044, U.S. Pat. No. 5,026,798, WO 92/00333and WO 93/19104 (corresponding to U.S. Ser. No. 8003, filed Jan. 21,1993 now U.S. Pat. No. 5,374,696).

EP-A-0,418,044, in example 3 and WO 92/00333 teach that bridgedmonocyclopentadienyl dihydrocarbyl Group 4 metal(+4) complexes can beprepared by hydrocarbylating the corresponding bridgedmonocyclopentadienyl Group 4 metal(+4) dihalide complexes with aGrignard, lithium, sodium or potassium salt of the hydrocarbyl ligand.The dihalide complexes in themselves are prepared by reacting the Group4 metal(+4) tetrahalide with a dianionic derivative of the bridgingmonocyclopentadienyl ligand. Alternative methods to prepare thesedihalide complexes are disclosed in EP-A-0,416,815 and EP-A-0,514,828which require reacting an ether adduct of a transition metal(+3)trihalide compound with the dianionic derivative of the cyclopentadienylligand, followed by contacting the resulting complex with anon-interfering oxidizing agent, such as for example AgCl(EP-A-0,416,815) or an organic halide (EP-A-0,514,828) to raise theoxidation state of the metal to form the desired metal(+4) dihalidecomplex.

The bridged monocyclopentadienyl monohydrocarbyl metal(+3) coordinationcomplexes can be prepared by hydrocarbylating the corresponding bridgedmonocyclopentadienyl metal(+3) monohalide coordination complexes with aGrignard, lithium, sodium or potassium salt of the hydrocarbyl ligand.The bridged monocyclopentadienyl metal(+3) monohalide complexesthemselves are prepared by reacting a Group 4 metal(+3) trihalidecompound, in the form of an ether adduct, with a dianionic derivative ofthe bridging monocyclopentadienyl ligand. Alternatively, the bridgedmonocyclopentadienyl monohydrocarbyl metal(+3) complexes are prepared bymonohydrocarbylating the corresponding bridged monocyclopentadienylmetal(+4) dihalide complexes with a Grignard, lithium, sodium orpotassium salt of the hydrocarbyl ligand, followed by reducing with ametal such as magnesium. These synthesis methods are described in WO93/19104 (corresponding to U.S. Ser. No. 8003, filed Jan. 21, 1993).

All of the synthesis methods described hereinbefore start from Group 4metal tri- or tetrahalide compounds which are corrosive, toxic, and airand moisture sensitive. In the presence of moisture these compoundsliberate HCl. In order to facilitate handling thereof, prior to thereaction step the transition metal tri- or tetrahalide compound istypically converted to its ether-adduct in a separate step with, forexample, THF or diethyl ether. This adduct formation step in itself isdifficult to perform on a large scale due to the high exothermicity ofthe reaction, requiring efficient cooling and low to very lowtemperatures and careful addition to prevent Lewis acid-catalyzedcleavage of the ether molecule, and an inert atmosphere. The adduct isusually recovered before it is reacted with the dianionic derivative ofthe bridged monocyclopentadienyl ligand compound.

In J. Organometal. Chem. 1976, 110, 321, A. Dormond et al. describe thereaction between bis(cyclopentadienyl) titanium(+4) dichloride and adianionic derivative of a bridged biscyclopentadienyl ligand, Na₂ C₅ H₄(CH₂)₃ C₅ H₄ !, to form a mixture of di-η⁵ -C₅ H₄ (CH₂)₃ C₅ H₄ !Ti (η¹-C₅ H₅)₂ and (η⁵ -C₅ H₅)₂ Ti di-η¹ -C₅ H₄ (CH₂)₃ C₅ H₄ !. Dormond et al.further disclose that bis(cyclopentadienyl) titanium(+4) bis(phenyl)when attacked by phenyl lithium forms the complex Cp₂ TiPh₃ !⁻ Li⁺ whichultimately decomposes to CpTiPh₂, CpLi and a phenyl radical.

DE-A-3,936,096 generically discloses the reaction betweenMeX'_(q).(solv')_(r), wherein Me could be Ti or Zr, X' could be Cl, Br,I, --OOCR', --OR', --NR'₂, -cyclopentadienyl, solv' is ether or tert.amine, q is 2-5, and r is 0-3, with a dialkali metal- or digrignardorgano compound to form homoleptic metallacyclic organometal compounds.

It would be desirable to develop an improved process to prepare mono- ordihydrocarbyl derivatives of bridged monocyclopentadienyl Group 4 metalcomplexes which process avoids the use of the corrosive, toxic, and airand moisture sensitive metal tetrahalide or trihalide startingcompounds, and avoids the formation of an ether adduct.

It would also be desirable to provide a process for the preparation ofmonohydrocarbyl derivatives of bridged monocyclopentadienyl Group 4metal(+3) complexes which process avoids the use of any Group 4metal(+4) compound or complex and thus requires fewer steps, such as areduction step from the +4 oxidation state to the +3 oxidation state.

It would yet further be desirable to provide certain novel stablebis(cyclopentadienyl) metal complexes which enable the desired mono- ordihydrocarbyl derivatives of bridged monocyclopentadienyl Group 4 metalcomplexes to be prepared. It would be furthermore desirable to providecertain novel stable bis(cyclopentadienyl) metal complexes which areuseful in catalyst compositions for addition polymerization processes.

SUMMARY OF THE INVENTION

Surprisingly, it has been found that bridged mono- and dihydrocarbylderivatives of monocyclopentadienyl Group 4 metal complexes can beprepared by nucleophilic substitution of correspondingbis(cyclopentadienyl) metal complexes.

According to the present invention there is provided a process for thepreparation of a monocyclopentadienyl metal complex corresponding to theformula: ##STR1## wherein: Cp* is a cyclopentadienyl group or asubstituted derivative of said cyclopentadienyl group wherein thesubstituent is a hydrocarbyl, silyl, amino, aminohydrocarbyl, halo,halohydrocarbyl, silylhydrocarbyl, hydrocarbylmetalloid orhalohydrocarbylmetalloid, said Cp* being covalently bonded to Z andπ-bonded to M and containing up to 50 nonhydrogen atoms;

Z is a divalent moiety comprising oxygen, nitrogen, phosphorous, boron,or a member of Group 14 of the Periodic Table of the Elements, saidmoiety having up to 30 nonhydrogen atoms and being covalently bonded toY and Cp*;

Y is a linking group comprising nitrogen, phosphorus, oxygen or sulfurcovalently bonded to M and Z through said nitrogen, phosphorus, oxygenor sulfur atom;

M is a metal of Group 4 of the Periodic Table of the Elements in anoxidation state of +3 or +4;

R independently each occurrence is a hydrocarbyl group, optionallysubstituted with one or more amino, phosphino, ether, thioether, orsilyl groups, said R having up to 50 nonhydrogen atoms, provided that Ris not a cyclopentadienyl group or substituted cyclopentadienyl group;

Q independently each occurrence is hydride, or a monovalent anionicligand selected from hydrocarbyl, silyl, amido and phosphido groups,said groups optionally being further substituted with one or more amino,phosphino, ether, ester, thioether, or silyl groups, said Q having up to50 nonhydrogen atoms, provided that Q is not a cyclopentadienyl group orsubstituted cyclopentadienyl group; and

m is 1 or 2; n is 0 or 1; and the sum of m and n is two less than theoxidation state of M;

the process comprising contacting in an aprotic solvent:

1) a bis(cyclopentadienyl Group 4 metal complex corresponding to theformula: ##STR2## wherein: Cp independently is a cyclopentadienyl groupor a substituted derivative of said cyclopentadienyl group wherein thesubstituent is hydrocarbyl, silyl, halo, amino, aminohydrocarbyl,halohydrocarbyl, silylhydrocarbyl, hydrocarbylmetalloid orhalohydrocarbylmetalloid, said Cp being π-bonded to M, and containing upto 50 nonhydrogen atoms;

X independently each occurrence is halo, hydrocarbyloxy, siloxy,carboxy, sulfido or sulfonato;

Cp*, Z, Y, M, Q, and n are as previously defined; and

t is 0 or 1; and the sum of n and t is three less than the oxidationstate of M; and

2) an alkali metal derivative or alkaline earth metal derivative of R,wherein R is as previously defined, to form the monocyclopentadienylcomplex of formula (I).

According to another aspect the present invention provides abis(cyclopentadienyl) Group 4 metal complex corresponding to theformula: ##STR3## wherein: Cp* is a cyclopentadienyl group or asubstituted derivative of said cyclopentadienyl group wherein thesubstituent is a hydrocarbyl, silyl, amino, aminohydrocarbyl, halo,halohydrocarbyl, silylhydrocarbyl, hydrocarbylmetalloid orhalohydrocarbylmetalloid, said Cp* being covalently bonded to Z andπ-bonded to M and containing up to 50 nonhydrogen atoms;

Z is a divalent moiety comprising oxygen, nitrogen, phosphorous, boron,or a member of Group 14 of the Periodic Table of the Elements, saidmoiety having up to 30 nonhydrogen atoms and being covalently bonded toY and Cp*, with the proviso that when M is zirconium then Z is not1,2-ethene-diyl or 1,3-propanediyl;

Y is a linking group comprising nitrogen, phosphorus, oxygen or sulfurcovalently bonded to M and Z through said nitrogen, phosphorus, oxygenor sulfur atom;

M is a metal of Group 4 of the Periodic Table of the Elements in anoxidation state of +3 or +4;

X independently each occurrence is halo, hydrocarbyloxy, siloxy,carboxy, sulfido or sulfonato;

Cp independently is a cyclopentadienyl group or a substituted derivativeof said cyclopentadienyl group wherein the substituent is hydrocarbyl,silyl, halo, amino, aminohydrocarbyl, halohydrocarbyl, silylhydrocarbyl,hydrocarbylmetalloid or halohydrocarbylmetalloid, said Cp being π-bondedto M, and containing up to 50 nonhydrogen atoms;

Q independently each occurrence is hydride, or a monovalent anionicligand selected from hydrocarbyl, silyl, amido and phosphido groups,said groups optionally being further substituted with one or more amino,phosphino, ether, ester, thioether, or silyl groups, said Q having up to50 nonhydrogen atoms, provided that Q is not a cyclopentadienyl group orsubstituted cyclopendienyl group;

n is 0 or 1; t is 0 or 1; and the sum of n and t is three less than theoxidation state of M.

According to yet a further aspect the present invention provides aprocess for preparing bis(cyclopentadienyl) Group 4 metal complexescorresponding to the formula: ##STR4## wherein: Cp* is acyclopentadienyl group or a substituted derivative of saidcyclopentadienyl group wherein the substituent is a hydrocarbyl, silyl,amino, aminohydrocarbyl, halo, halohydrocarbyl, silylhydrocarbyl,hydrocarbylmetalloid or halohydrocarbylmetalloid, said Cp* beingcovalently bonded to Z and π-bonded to M and containing up to 50nonhydrogen atoms;

Z is a divalent moiety comprising oxygen, nitrogen, phosphorous, boron,or a member of Group 14 of the Periodic Table of the Elements, saidmoiety having up to 30 nonhydrogen atoms and being covalently bonded toY and Cp*;

Y is a linking group comprising nitrogen, phosphorus, oxygen or sulfurcovalently bonded to M and Z through said nitrogen, phosphorus, oxygenor sulfur atom;

M is a metal of Group 4 of the Periodic Table of the Elements in anoxidation state of +3 or +4;

Q independently each occurrence is hydride, or a monovalent anionicligand selected from hydrocarbyl, silyl, amido and phosphido groups,said groups optionally being further substituted with one or more amino,phosphino, ether, ester, thioether, or silyl groups, said Q having up to50 nonhydrogen atoms, provided that Q is not a cyclopentadienyl group ora substituted cyclopentadienyl group;

Cp independently is a cyclopentadienyl group or a substituted derivativeof said cyclopentadienyl group wherein the substituent is hydrocarbyl,silyl, halo, amino, aminohydrocarbyl, halohydrocarbyl, silylhydrocarbyl,hydrocarbylmetalloid or halohydrocarbylmetalloid, said Cp being π-bondedto M, and containing up to 50 nonhydrogen atoms;

X independently each occurrence is halo, hydrocarbyloxy, siloxy,carboxy, sulfido or sulfonato;

n is 0 or 1; t is 0 or 1; and the sum of n and t is three less than theoxidation state of M;

the process comprising contacting in an aprotic organic solvent: i) acompound corresponding to one of the formulas (Cp)₃ MQ_(n) X_(t), (Cp)₂MQ_(n) X_(t+1), or CpMQ_(n) X_(t+2) or a neutral Lewis base coordinatedadduct thereof, wherein: n is 0 or 1; t is 0 or 1; the sum of n and t isthree less than the valence of M; and Cp, M, Q and X are as previouslydefined; and ii) a dianionic salt compound corresponding to the formula:(L^(+x))_(y) (Cp*-Z-Y)⁻² or ((LX')^(+x))_(y) (Cp*-Z-Y)⁻² wherein L is ametal of Group 1 or 2 of the Periodic Table of the Elements; X'independently is chloro, bromo, or iodo; x is 1 or 2, y is 1 or 2, andthe product of x and y equals 2; and Cp*, Z, and Y are as previouslydefined; to form the complex of formula (II).

According to a further aspect, the present invention provides anaddition polymerization catalyst composition comprising abis(cyclopentadienyl) Group 4 metal coordination complex as describedhereinbefore and an activating cocatalyst.

According to another aspect, the present invention provides a processfor addition polymerization of one or more addition polymerizablemonomers, wherein a catalyst composition as described hereinbefore iscontacted with one or more addition polymerizable monomers underconditions promoting addition polymerization.

DETAILED DESCRIPTION

All reference to the Periodic Table of the Elements herein shall referto the Periodic Table of the Elements, published and copyrighted by CRCPress, Inc., 1989. Also, any reference to a Group or Groups shall be tothe Group or Groups as reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups.

The recitation "metalloid", as used herein, refers to boron, phosphorus,silicon, germanium, and arsenic.

Generally, the Group 4 metal is titanium, zirconium, or hafnium.Preferably it is titanium or zirconium, and most preferably titanium.

Each of up to four of the five carbon atoms making up the five memberedring in the cyclopentadienyl Cp* group independently may beunsubstituted or substituted with the same or a different radicalselected from the group consisting of hydrocarbyl radicals, halogenradicals, silyl radicals, amino radicals, substituted hydrocarbylradicals wherein one or more hydrogen atoms are replaced by a halogenatom, amino radical or silyl radicals, hydrocarbyl-substituted metalloidradicals, and halohydrocarbyl-substituted metalloid radicals. Preferredhydrocarbyl and substituted hydrocarbyl radicals contain from 1 to 20carbon atoms and include linear, branched, cyclic, or alkyl-substitutedcyclic, aliphatic hydrocarbon radicals, aromatic radicals andalkyl-substituted aromatic radicals. Suitable hydrocarbyl-substitutedmetalloid radicals include mono-, di- and trihydrocarbyl substitutedmetalloid radicals wherein each of the hydrocarbyl groups contains from1 to about 20 carbon atoms. More particularly, suitablehydrocarbyl-substituted metalloid radicals include trimethylsilyl,triethylsilyl, ethyldimethylsilyl, methyldiethylsilyl, triphenylgermyl,trimethylgermyl and the like. Adjacent substituents in thecyclopentadienyl Cp* may be linked together thereby forming an indenyl,tetrahydroindenyl, fluorenyl, tetrahydrofluorenyl, or octahydrofluorenylgroup in place of the cyclopentadienyl group.

The bridging monocyclopentadienyl ligand moiety consisting of -Cp*-Z-Y-is a dianionic ligand having ionic charges residing formally on Cp* andY. Such ligand causes the resulting complex to possess unique propertiesabout the active metal catalyst site resulting in highly active Group 4metal catalysts. These ligands and complexes containing the same arefurther described in U.S. patent application Ser. No. 545,403, filedJul. 3, 1990, (corresponding to EP-A-0,416,815) and U.S. Ser. No. 8003,filed Jan. 21, 1993 (corresponding to WO 93/19104) which areincorporated herein by reference.

Q independently each occurrence preferably is: hydride; primary,secondary or tertiary alkyl; aryl; aralkyl; trialkylsilylalkyl;alkoxyalkyl; alkyl(polyalkyleneoxy)alkyl; dialkylaminoalkyl;dialkylaminoaralkyl; allyl; alkyl-substituted allyl; alkadienyl;alkyl-substituted alkadienyl; dialkylphosphinoalkyl; ordialkylphosphinoaralkyl, said Q having up to 20 nonhydrogen atoms. Morepreferably Q is a hydrocarbyl of up to 20 carbons.

Q may be present in the bis(cyclopentadienyl) complex of formula (II).Usually, Q will not be replaced by R when the complex of formula (II) iscontacted with the nucleophilic reactant, i.e., the alkali metalderivative or alkaline earth metal derivative of ligand R. Thesubstituent X which may be present in the complex of formula (II),however, will be replaced by said nucleophilic reactant when contactedwith the nucleophilic reactant.

In general R independently each occurrence is a covalently bondedhydrocarbyl group, optionally substituted with one or more amino,phosphino, ether, thioether, or silyl groups, said R having up to 50nonhydrogen atoms, provided that R is not a cyclopentadienyl group orsubstituted cylcopentadienyl group. Preferably R is: primary, secondaryor tertiary alkyl; aryl; aralkyl; trialkylsilylalkyl; alkoxyalkyl;alkyl(polyalkyleneoxy)alkyl; dialkylaminoalkyl; dialkylaminoaralkyl;allyl; alkyl-substituted allyl; alkadienyl; alkyl-substitutedalkadienyl; dialkylphosphinoalkyl; or dialkylphosphinoaralkyl, said Rhaving up to 20 nonhydrogen atoms. Most preferably R is hydrocarbyl ofup to 20 carbons.

X preferably is halide, especially chloride, or alkoxide or aryloxide,preferably a C₁₋₈ alkoxide such as for example methoxide, ethoxide,isopropoxide, n- and tert-butoxide.

Cp in the complex of formula (II) is a cyclopentadienyl group π-bondedto M or is a cyclopentadienyl group π-bonded to M which is substitutedwith one or more of the same or different radicals selected from thegroup consisting of amino radicals, halogen radicals, hydrocarbylradicals, substituted-hydrocarbyl radicals wherein one or more hydrogenatoms is replaced by a halogen atom or a silyl group, an amino radical,hydrocarbyl-substituted metalloid radicals, andhalohydrocarbyl-substituted metalloid radicals. Adjacent substituents inthe cyclopentadienyl Cp may be linked together thereby forming anindenyl, tetrahydroindenyl, fluorenyl, tetrahydrofluorenyl, oroctahydrofluorenyl group in place of the cyclopentadienyl group.

According to the present process more preferably a monocyclopentadienylcomplex corresponding to the formula: ##STR5## wherein: R' eachoccurrence is independently selected from the group consisting ofhydrogen, silyl, hydrocarbyl, or silyl-substituted hydrocarbyl having upto 10 carbon or silicon atoms;

E independently each occurence is silicon or carbon;

Q is allyl, alkyl-substituted allyl, pentadienyl, alkyl-substitutedpentadienyl, or an alkyl, aryl, aralkyl, silyl, trialkylsilylalkyl, ordialkylaminoaralkyl group, said group having up to 10 carbons;

R is allyl, alkyl-substituted allyl, pentadienyl, alkyl-substitutedpentadienyl, or an alkyl, aryl, aralkyl, silyl, trialkylsilylalkyl, ordialkylaminoaralkyl group, said group having up to 10 carbons; and

a is 1 or 2; m is 1 or 2; n is 0 or 1; and the sum of m and n is twoless than the oxidation state of titanium;

is prepared by contacting:

1) a bis(cyclopentadienyl) Group 4 metal complex corresponding to theformula: ##STR6## wherein: R', E, Q, n, and a are as previously defined;

t is 0 or 1;

X and Cp are as defined for formula (II); and

the sum of n and t is three less than the oxidation state of titanium;and

2) the alkali metal derivative or alkaline earth metal derivative ofligand R.

Preferably R' on the foregoing cyclopentadienyl groups each occurrenceis hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, includingisomers of these radicals, norbornyl, benzyl, phenyl, or two such R'groups together are a C₃ or C₄ hydrocarbylene moiety forming a fusedring with adjacent carbons of the cyclopentadienyl group.

In the bridged monocyclopentadienyl complexes of formula (I) or (Ia),preferably m is 1 or 2 and n is 0. These are prepared from thecorresponding bis(cyclopentadienyl) complexes of formula (II) or (IIa)wherein preferably n is 0, and t is 0 or 1.

Highly preferred bridged monocyclopentadienyl complexes of formula (I)or (Ia) are those wherein m is 1 and n is 0. These are the Group 4 metalcomplexes, and especially the titanium complexes, having a +3 oxidationstate. These are prepared from the corresponding bis(cyclopentadienyl)complexes of formula (II) or (IIa) wherein n is 0, and t is 0.

The present process, especially in combination with the preferredprocess to make the bis(cyclopentadienyl) Group 4 metal complexes offormulas (II) and (IIa), which will be described in more detailhereinafter, is capable of preparing the bridged monocyclopentadienylGroup 4 metal monohydrocarbyl complexes in the +3 oxidation state ingood yield while avoiding Group 4 metal tri- or tetrahalide startingcompounds and the reduction step which would be required when startingfrom a Group 4 metal compound in the +4 oxidation state.

It has been found highly desirable when M is Ti(+3), that R should becapable of stabilizing the resulting complex. Exemplary R groups capableof stabilizing the resulting complex are ligands comprising an amino,phosphino, ether or thioether functionality capable of forming acoordinate-covalent bond or chelating bond with Ti, or comprising anethylenic unsaturation capable of forming a π-bond, more particularly anη3 or η5 bond, with Ti. R preferably is allyl or alkyl-substitutedallyl, alkadienyl or alkyl-substituted alkadienyl all of which areπ-bonded to M, or amino-, phosphino- or alkoxy-substituted hydrocarbylof up to 20 carbon atoms. More preferably R is an alkyl-substitutedallyl, alkyl-substituted pentadienyl both of which are π-bonded to M, ordialkyl-aminoaralkyl group, most preferably 2-(N,N-dimethylamino)benzyl.The stabilizing R groups are further described in U.S. Ser. No. 8003,filed Jan. 21, 1993 (corresponding to WO 93/19104).

In the bis(cyclopentadienyl) complexes of formula (II) or (IIa) Cp ispreferably cyclopentadienyl or a C₁₋₆ substituted cyclopentadienyl.

Examples of the above highly preferred Group 4 metal complexes offormula (Ia) include compounds wherein the R' on the amido group ismethyl, ethyl, propyl, butyl, pentyl, hexyl, including isomers of theseradicals, norbornyl, benzyl, phenyl, etc.; the cyclopentadienyl group(including R' substituents) is cyclopentadienyl,tetramethylcyclopentadienyl, indenyl, tetrahydroindenyl, fluorenyl,octahydrofluorenyl, etc.; and R is methyl, neopentyl, trimethylsilyl,trimethylsilylmethyl, norbornyl, benzyl, methylbenzyl, phenyl,2-(N,N-dimethylamino)benzyl, allyl, 2-methylpentadienyl,2,4-dimethylpentadienyl, etc. When R is allyl, substituted allyl,pentadienyl, or substituted pentadienyl and the Group 4 metal complex isin the +3 oxidation state, then R is π-bonded to M.

Specific titanium(+3) complexes of formula (Ia) that can be preparedaccording to the present process include: (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(N,N-dimethylamino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(N,N-dimethylamino)benzyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium2-(N,N-dimethylamino)benzyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(N,N-dimethylamino)benzyl,(methylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium2-(N,N-dimethylamino)benzyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(N,N-dimethylamino)benzyl,(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium allyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium allyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl!titaniumallyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium allyl, (methylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium allyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium allyl, (phenylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium methyl, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(dimethylphosphino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(dimethylphosphino)benzyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium2-(dimethylphosphino)benzyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)- 1,2-ethanediyl!titanium 2-(dimethylphosphino)benzyl,(methylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium2-(dimethylphosphino)benzyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium 2-(dimethylphosphino)benzyl,(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium2-(N,N-bis(pentafluorophenyl)amino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium2-(N,N-bis(trimethylsilyl)amino)benzyl, (tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium 2-(N,N-dimethylamino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium 2-(N,N-dimethylamino)benzyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)dimethylsilane!titanium2-(N,N-dimethylamino)benzyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium 2-(N,N-dimethylamino)benzyl,(methylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium2-(N,N-dimethylamino)benzyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium 2-(N,N-dimethylamino)benzyl,(tert-butylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium allyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium allyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)dimethylsilane!titaniumallyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium allyl, (methylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium allyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium allyl, (tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium 2-(dimethylphosphino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium 2-(dimethylphosphino)benzyl,(tert-butylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium2-(N,N-bis(pentafluorophenyl)amino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium2-(N,N-bis(pentafluorophenyl)amino)benzyl, and (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium2-(N,N-bis(trimethylsilyl)amino)benzyl, and the like.

Specific titanium(+4) complexes of formula (Ia) that can be preparedaccording to the present process include: (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium dimethyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium dibenzyl,(methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)2-(N,N-dimethylamino)benzyl, (methylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium dimethyl,(methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl)2-(N,N-dimethylamino)benzyl, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)allyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium dimethyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl!titaniumdibenzyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl)allyl,(phenylamido)(ethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl!titaniumdimethyl, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium dibenzyl,(phenylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(2-(dimethylphosphino)benzyl)allyl,(tert-butylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)2-(dimethylphosphino)benzyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl)2-(dimethylphosphino)benzyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium dibenzyl,(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)2-(N,N-bis(pentafluorophenyl)amino)benzyl, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(phenyl)2-(N,N-dimethylamino)benzyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)2-(N,N-bis(trimethylsilyl)amino)benzyl, (tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium dibenzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium dibenzyl,(tert-butylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)2-(N,N-dimethylamino)benzyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium dimethyl, (methylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium dibenzyl,(methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(benzyl)methyl,(tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium(allyl)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)phenyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)dimethylsilane!titaniumdimethyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(allyl)phenyl, (methylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)allyl,(methylamido)(ethyl-η⁵ -cyclopentadienyl)dimethylsilane!titaniumdimethyl, (tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)2-(dimethylphosphino)benzyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(benzyl)2-(dimethylphosphino)benzyl, (tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)2-(N,N-bis(pentafluorophenyl)amino)benzyl,(tert-butylamido)(tetramethyl-η ⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)2-(N,N-bis(pentafluorophenyl)amino)benzyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl)2-(N,N-bis(trimethylsilyl)amino)benzyl, and the like.

Other bridged monocyclopentadienyl Group 4 metal complexes that may beprepared according to the present invention will, of course, be apparentto those skilled in the art.

The alkali metal derivative or alkaline earth metal derivative of ligandR, i.e., the nucleophilic reactant, suitably is the lithium, sodium,potassium, magnesium or magnesium halo (Grignard) salt of the group R.Preferably the alkali metal derivative or alkaline earth metalderivative of R is a compound of the formula LiR, MgR₂, or MgX"R,wherein R is as previously defined and X" is halogen, preferably chloroor bromo, most preferably chloro. Specific preferred examples of thesenucleophilic reactants include: methyl lithium, benzyl lithium, phenyllithium, 2-(N,N-dimethylamino)benzyl lithium, allyl lithium,2-(dimethylphosphino)benzyl lithium,2-(N,N-bis(pentafluorophenyl)amino)benzyl lithium,2-(N,N-bis(trimethylsilyl)amino)benzyl lithium, methyl magnesiumchloride, benzyl magnesium chloride, phenyl magnesium chloride,2-(N,N-dimethylamino)benzyl magnesium chloride, allyl magnesiumchloride, 2,4-dimethylpentadienyl potassium, pentadienyl lithium,2-(dimethylphosphino)benzyl magnesium chloride,2-(N,N-bis(pentafluorophenyl)amino)benzyl magnesium chloride,2-(N,N-bis(trimethylsilyl)amino)benzyl magnesium chloride, and the like.

In general, the bridged monocyclopentadienyl complexes can be preparedby contacting the bis(cyclopentadienyl) metal complex and thenucleophilic reactant in a suitable aprotic organic solvent. Therelative amounts of bis(cyclopentadienyl) metal complex and nucleophilicreactant used may vary considerably, however, the best yields aregenerally obtained when using a stoichiometric molar quantity, or aslight stoichiometric molar excess of the nucleophilic reactant.Accordingly, preferably from 0.95 to 1.2 molar equivalents ofnucleophilic reactant are used per molar equivalent of Cp and X on M,more preferably from 1.0 to 1.1 molar equivalents.

Suitable reaction media for the formation of the bridgedmonocyclopentadienyl complexes are hydrocarbons and ethers. Examplesinclude straight and branched-chain hydrocarbons such as isobutane,butane, pentane, hexane, heptane, octane, and mixtures thereof; cyclicand alicyclic hydrocarbons such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof; aromaticand alkyl-substituted aromatic compounds such as benzene, toluene,xylene and the like; C₁₋₄ dialkyl ethers, C₁₋₄ dialkyl ether derivativesof (poly)alkylene glycols, and cyclic ethers such as tetrahydrofuran.Mixtures of the foregoing are also suitable. More preferably the aproticsolvent is selected from the group consisting of ethers and aliphatic,cycloaliphatic, aromatic and alkyl-aromatic hydrocarbons. Mostpreferably, the solvent is diethyl ether or tetrahydrofuran.

The process to prepare the bridged monocyclopentadienyl complexes isusually conducted at a temperature from -78° C. to 150° C., preferablybetween -25° C. and 100° C., most preferably between 0° C. and 50° C.The time of reaction may vary from a few minutes to several days, but isgenerally a few hours.

The recovery procedure for the bridged monocyclopentadienyl complexesinvolves separation from the resulting alkali metal or alkaline earthmetal salt and from the reaction medium. Typically, the byproduct saltsare the alkali metal or alkaline earth metal salts of Cp and X, ifpresent in the bis(cyclopentadienyl) metal complex. The byproduct saltsmay be separated from the desired product by precipitation andfiltration, extraction into a secondary solvent or other separationtechnique, depending of course on the differences between the solubilitycharacteristics of both the desired product and byproduct salts. Therecovery procedure is facilitated by the use of reaction media that aresolvents for the resulting bridged monocyclopentadienyl complex but arenon-solvents for the resulting byproducts, or vice versa. A preferredexample of such a solvent in which the desired product is soluble butthe alkali metal or alkaline earth metal cyclopentadienide saltgenerally is not is hexane.

According to a preferred embodiment of the present process, andaccording to a further aspect of the present invention, a process isprovided for the preparation of the bridged bis(cyclopentadienyl) Group4 metal coordination complexes of formula (II) and (IIa) by contactingin an aprotic organic solvent: i) a compound corresponding to one of theformulas (Cp₃)MQ_(n) X_(t), (Cp)₂ MQ_(n) X_(t+1), or CpMQ_(n) X_(t+2) ora neutral Lewis base coordinated adduct thereof: wherein n is 0 or 1, tis 0 or 1, and the sum of n and t is three less than the oxidation stateof M, wherein M, Cp, X, and Q are as previously defined; and ii) adianionic salt compound corresponding to the formula:(L^(+x))_(y)(Cp*-Z-Y)⁻² or ((LX')^(+x))_(y) (Cp*-Z-Y)⁻² wherein L is ametal of Group 1 or 2 of the Periodic Table of the Elements; X'independently is chloro, bromo, or iodo; x is 1 or 2, y is 1 or 2, andthe product of x and y equals 2; and Cp*, Z, and Y are as previouslydefined.

Preferably, in the compounds of formulas (Cp)₃ MQ_(n) X_(t), (Cp)₂MQ_(n) X_(t+1), or CpMQ_(n) X_(t+2) n is 0 and t is 0 or 1. Exemplary ofsuch compounds are tris(η⁵ -cyclopentadienyl)titanium and tris(η⁵-cyclopentadienyl)titanium monohalide, bis(η⁵ -cyclopentadienyl)titaniummono- and di-halides, bis(η⁵ -cyclopentadienyl)titanium mono- anddi-alkoxides, (η⁵ -cyclopentadienyl)titanium di- and tri-halides, (η⁵-cyclopentadienyl)titanium di- and tri-alkoxides, as well as theanaloguous zirconium and hafnium compounds. Most preferably, in theabove formulas both n and t are 0. Exemplary of neutral Lewisbase-coordinated adducts of these compounds are the ether adducts of (η⁵-cyclopentadienyl)titanium dihalides.

The process has been found especially suitable to prepare thebis(cyclopentadienyl) Group 4 metal complexes of formulas (II) and (IIa)wherein the metal is in the +3 oxidation state. More preferably, in thepresent process M is Ti(+3), n is 0, and t is 0. Most preferably, in thepresent process (Cp)₃ Ti or (Cp)₂ TiX is used wherein Cp iscyclopentadienyl and is η⁵ -bonded to titanium, and X is chloro.

Preferred examples of the dianionic salt compound corresponding to theformula: (L^(+x))(Cp*-Z-Y)⁻² or ((LX')^(+x))_(y) (Cp*-Z-Y)⁻² include:(tert-butylamido)(cyclopentadienyl)-1,2-ethanediyl dilithium ordi(magnesiumchloride),(tert-butylamido)(tetramethylcyclopentadienyl)-1,2-ethanediyl dilithiumor di(magnesiumchloride),(methylamido)(tetramethylcyclopentadienyl)-1,2-ethanediyl dilithium ordi(magnesiumchloride), (methylamido)(cyclopentadienyl)-1,2-ethanediyldilithium or di(magnesiumchloride),(methylamido)(ethylcyclopentadienyl)-1,2-ethanediyl dilithium ordi(magnesiumchloride), (tert-butylamido)(cyclopentadienyl)dimethylsilanedilithium or di(magnesiumchloride),(tert-butylamido)(tetramethylcyclopentadienyl)dimethylsilane dilithiumor di(magnesiumchloride),(tert-butylamido)(ethylcyclopentadienyl)dimethylsilane dilithium ordi(magnesiumchloride),(methylamido)(tetramethylcyclopentadienyl)dimethylsilane dilithium ordi(magnesiumchloride), (methylamido)(cyclopentadienyl)dimethylsilanedilithium or di(magnesiumchloride),(methylamido)(ethylcyclopentadienyl)dimethylsilane dilithium ordi(magnesiumchloride), (phenylamido)(cyclopentadienyl)dimethylsilanedilithium or di(magnesiumchloride),(phenylamido)(tetramethylcyclopentadienyl)dimethylsilane dilithium ordi(magnesiumchloride),(phenylamido)(ethylcyclopentadienyl)dimethylsilane dilithium ordi(magnesiumchloride), and the like.

The dianionic salt compounds used in the present process are knowncompounds and can be synthesized as described in EP-A-0,416,815 or U.S.Pat. No. 5,026,798.

In general, the bis(cyclopentadienyl) metal complexes of formula (II)and (IIa) can be prepared by contacting the compound of formulas (Cp)₃MQ_(n) X_(t), (Cp)₂ MQ_(n) X_(t+1), or CpMQ_(n) X_(t+2) with thedianionic salt compound in a suitable aprotic organic liquid diluent.The relative amounts of the compound of formulas (Cp)₃ MQ_(n) X_(t),(Cp)₂ MQ_(n) X_(t+1), or CpMQ_(n) X_(t+2) and dianionic salt compoundused may vary considerably, however, the best yields are generallyobtained when using a stoichiometric molar quantity, or a slightstoichiometric molar excess of the dianionic salt compound. Preferablyfrom 0.95 to 1.2 molar equivalents of the dianionic salt are used permolar equivalent of the coreactant, more preferably 1.0 to 1.1 molarequivalent.

Suitable aprotic organic solvents are hydrocarbons and ethers. Examplesinclude straight and branched-chain hydrocarbons such as isobutane,butane, pentane, hexane, heptane, octane, and mixtures thereof; cyclicand alicyclic hydrocarbons such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof; aromaticand alkyl-substituted aromatic compounds such as benzene, toluene,xylene and the like, C₁₋₄ dialkyl ethers, C₁₋₄ dialkyl ether derivativesof (poly)alkylene glycols, and cyclic ether such as tetrahydrofuran.Mixtures of the foregoing are also suitable. More preferably the aproticsolvent is selected from the group consisting of ethers and aliphatic,cycloaliphatic, aromatic and alkyl-aromatic hydrocarbons, preferablyC₅₋₁₀ hydrocarbons. Most preferably, the ether is diethyl ether ortetrahydrofuran.

The process to prepare the bis(cyclopentadienyl) metal complexes offormula (II) or (IIa) is usually conducted at a temperature from -78° C.to 150° C., preferably between -25° C. and 100° C., most preferably from0° C. to 50° C. The time of reaction may vary from a few minutes toseveral days, but is generally a few hours.

The bis(cyclopentadienyl) metal complexes of formula (II) or (IIa)prepared according to the present process may be recovered or used assuch in the process to prepare the bridged monocyclopentadienylcomplexes of formula (I). When used as component in a catalyst systemthe bis(cyclopentadienyl) metal complexes of formula (II) are preferablyrecovered and purified. The recovery procedure for thebis(cyclopentadienyl) metal complexes involves separation from theresulting alkali metal or alkaline earth metal salt (LX and optionallyLCp) and from the reaction medium. The separation of the byproduct saltsfrom the desired product may occur by methods known to those skilled inthe art, such as precipitation and filtration, extraction into asecondary solvent or other separation technique, depending of course onthe differences between the solubility characteristics of both thedesired product and byproduct salts. The recovery procedure isfacilitated by the use of reaction media that are solvents for theresulting bridged monocyclopentadienyl complex but are non-solvents forthe resulting byproducts, or vice versa. A preferred example of such asolvent in which the desired product is soluble, but the alkali metal oralkaline earth metal halidide or alkoxide salt is not, is hexane.

The bis( cyclopentadienyl ) Group 4 metal complexes in the +3 and +4oxidation states can be readily converted to one another by use of anappropriate oxidation agent, such as for example lead(II) chloride, oran appropriate reducing agent, such as for example magnesium metal.

According to a further aspect, the present invention provides novelbridged bis(cyclopentadienyl) Group 4 metal coordination complexes offormula (II) as previously defined herein. More preferably the bridgedbiscyclopentadienyl Group 4 metal coordination complexes correspond toformula (IIa) as previously defined herein.

Specific titanium(+3) complexes of formula (IIa) include:(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium η⁵-cyclopentadienyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium η⁵ -cyclopentadienyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium η⁵-cyclopentadienyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium η⁵ -cyclopentadienyl,(methylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium η⁵-cyclopentadienyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium η⁵ -cyclopentadienyl,(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titaniumpentamethyl-η⁵ -cyclopentadienyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium pentamethyl-η⁵-cyclopentadienyl, (tert-butylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium pentamethyl-η⁵-cyclopentadienyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium pentamethyl-η⁵-cyclopentadienyl, (methylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium pentamethyl-η⁵-cyclopentadienyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium pentamethyl-η⁵-cyclopentadienyl, (phenylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium η⁵ -cyclopentadienyl,(tert-butylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium η⁵-cyclopentadienyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium η⁵ -cyclopentadienyl,(tert-butylamido)(ethyl-η⁵ -cyclopentadienyl)dimethylsilane!titanium η⁵-cyclopentadienyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium η⁵ -cyclopentadienyl,(methylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium η⁵-cyclopentadienyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium η⁵ -cyclopentadienyl,(tert-butylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titaniumpentamethyl-η⁵ -cyclopentadienyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium pentamethyl-η⁵-cyclopentadienyl, (tert-butylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium pentamethyl-η⁵-cyclopentadienyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium pentamethyl-η⁵-cyclopentadienyl, (methylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium pentamethyl-η⁵-cyclopentadienyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium pentamethyl-η⁵-cyclopentadienyl, and the like.

Specific titanium(+4) complexes of formula (IIa) include:(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)η⁵ -cyclopentadienyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl) η⁵ -cyclopentadienyl,(methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵ -cyclopentadienyl)2-(N,N-dimethylamino)benzyl, (methylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl) η⁵ -cyclopentadienyl,(methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl)(η⁵ -cyclopentadienyl,(tert-butylamido)(η⁵ -cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)chloride, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)chloride, (tert-butylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)chloride, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)chloride, (phenylamido)-(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)chloride, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)pentamethyl-η⁵-cyclopentadienyl, (phenylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(2-(dimethylphosphino)benzyl)η⁵ -cyclopentadienyl, (tert-butylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl)pentamethyl-η⁵-cyclopentadienyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(benzyl)pentamethyl-η⁵-cyclopentadienyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(methyl)pentamethyl-η⁵-cyclopentadienyl, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(pentamethyl-η⁵-cyclopentadienyl)chloride, (tert-butylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)isopropoxide, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyl!titanium(η⁵-cyclopentadienyl)n-butoxide, (tert-butylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium(benzyl) η⁵ -cyclopentadienyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(benzyl) η⁵ -cyclopentadienyl,(tert-butylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl) η⁵ -cyclopentadienyl,(methylamido)(ethyl-η⁵ -cyclopentadienyl)dimethylsilane!titanium(methyl)η⁵ -cyclopentadienyl, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(methyl) η⁵ -cyclopentadienyl,(methylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium(benzyl) η⁵-cyclopentadienyl, (methylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(η⁵ -cyclopentadienyl)chloride,(tert-butylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium(η⁵-cyclopentadienyl)chloride, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(η⁵-cyclopentadienyl)isopropoxide, (tert-butylamido)(ethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(pentamethyl-η⁵-cyclopentadienyl)chloride, (methylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(pentamethyl-η⁵-cyclopentadienyl)n-butoxide, (methylamido)(η⁵-cyclopentadienyl)dimethylsilane!titanium(η⁵ -cyclopentadienyl)chloride,(tert-butylamido)(η⁵ -cyclopentadienyl)dimethylsilane!titanium(η⁵-cyclopentadienyl) 2-(dimethylphosphino)benzyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(η⁵ -cyclopentadienyl)2-(N,N-dimethylamino)benzyl, (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!(cyclopentadienyl)titanium acetate,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(trimethylsiloxy),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)trimethylsilyl,(tert-butylamido)(tetramethyl-η⁵ -cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)trimethylsilylmethyl,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(ethylthiolate),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(methyl) andthe like.

Other bis(cyclopentadienyl) Group 4 metal complexes of formulas (II) and(IIa) according to the present invention will, of course, be apparent tothose skilled in the art.

Highly preferred complexes of formula (IIa) include:(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)chloride,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)bromide,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(methyl),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(2-(N,N-dimethylamino)benzyl),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(trimethylsilylmethyl),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!titanium(cyclopentadienyl)(allyl),(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!zirconium(cyclopentadienyl)chloride,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilane!zirconium(cyclopentadienyl)(2-(N,N-dimethylamino)benzyl).

The bis(cyclopentadienyl) Group 4 metal complexes corresponding to theformulas (II) and (IIa) can be prepared, for example, by contacting thecorresponding bridged monocyclopentadienyl Group 4 metal halide ordihalide complex with L^(+x) Cp_(y) or (LX')^(+x) Cp_(y), wherein L, X',x and y are as previously defined and x=y. This method, however,inherently has the disadvantages associated with the preparation of thebridged monocyclopentadienyl Group 4 metal halide or dihalide complexesas mentioned hereinbefore. A preferred method for preparing the novelbis(cyclopentadienyl) Group 4 metal complexes of formulas (II) and (IIa)is described hereinbefore.

The bis(cyclopentadienyl) metal complexes of formula (II) or (IIa) mayfurther be used, preferably in combination with an activatingcocatalyst, in the addition polymerization of one or more additionpolymerizable monomers. Exemplary of addition polymerizable monomersinclude ethylenically unsaturated monomers, for example olefins and morespecifically α-olefins, conjugated or non-conjugated diolefins,acetylenically unsaturated monomers, and vinyl-aromatic monomers. In thepresent process one monomer can be polymerized or more than onedifferent type of monomer can be interpolymerized. The terminterpolymerization as used in the present application refers to apolymerization wherein at least two different monomers are used. Thesedifferent monomers can be of the same type of monomer, such asα-olefins, for example ethylene and 1-octene, or from different types ofmonomers such as α-olefins and vinylaromatic monomers, for exampleethylene and styrene, or α-olefins and diolefins. Preferably, themonomers have from 2 to 20 carbon atoms. Preferred monomers include theC₂₋₁₀ α-olefins, especially ethylene, propylene, isobutylene, 1-butene,1-hexene, 4-methyl-1-pentene, and 1-octene and mixtures thereof. Otherpreferred monomers include styrene, C₁₋₄ alkyl substituted styrene,vinylbenzocyclobutene, ethylidenenorbornene and 1,4-hexadiene. Thecatalyst composition of the present invention comprises abis(cyclopentadienyl) metal complex of formula (II) or (IIa) and anactivating cocatalyst, such as an aluminoxane, or a cocatalyst capableof converting the complex of formula (II) or (IIa) to a cationicderivative or by a combination of the foregoing cocatalysts. A preferredtechnique is to employ as cocatalyst an aluminoxane or approximatelystoichiometric amounts or slight excess of a strong Lewis acidactivating agent, preferably tris(pentafluorophenyl)borane, or mixturesthereof. In general, the polymerization may be accomplished atconditions well known in the prior art for Ziegler-Natta orKaminsky-Sinn type polymerization reactions, i.e., temperatures from 0°C.-250° C. and pressures from atmospheric to 1000 atmospheres.Suspension, solution, slurry, gas phase or other process conditions maybe employed if desired. A support may be employed but preferably thecatalysts are used in a homogeneous manner. Suitable cocatalysts andpolymerization conditions are disclosed in U.S. application Ser. No.545,403, filed Jul. 3, 1990 (EP-A-416,815), U.S. application Ser. No.547,718 filed Jul. 3, 1990 now abandoned (EP-A-468,651), U.S.application Ser. No. 702,475, filed May 20, 1991 now abandoned(EP-A-516,828), U.S. application Ser. No. 876,268, filed May 1, 1992(EP-A-520,732), and U.S. application Ser. No. 8,003, filed Jan. 21, 1993(WO 92/19104), as well as U.S. Pat. Nos. 5,055,438, 5,057,475,5,096,867, 5,064,802 and 5,132,380, all of which are incorporated hereinby reference.

In most polymerization reactions the equivalent ratio ofcatalyst:polymerizable compound employed is from 10⁻¹² :1 to 10⁻¹ :1,more preferably from 10⁻⁸ :1 to 10⁻⁵ :1.

Having described the invention the following examples are provided asfurther illustration thereof and are not to be construed as limiting.Unless stated to the contrary all parts and percentages are expressed ona weight basis. All metal complex preparations were performed under aninert atmosphere of argon or nitrogen.

PART A: Preparation of Complexes of Formula (IIa)

EXAMPLE 1 (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+3)(cyclopentadienyl)

Preparation A:

1.911 g (3.71 mmol) of (MgCl.THF)₂ (C₅ Me₄ SiMe₂ NCMe₃) (preparedaccording to EP-A-514,828) and 1.380 g (3.72 mmol) of TiCl₃ (THF)₃(prepared according to Inorg. Syn. 1982, 21, 135) were combined in aflask with 70 mL of THF to give a dark solution. After stirring for 5minutes, 2.07 mL (3.73 mmol) of 1.80M sodium cyclopentadienide solutionin THF was added. The resulting pale yellow solution was stirred for 16hours. The solvents were removed under reduced pressure. The residue wasextracted with pentane, filtered and concentrated. After chilling for 16hours at -40° C. a yellow-green microcrystalline product was collectedon a frit and dried under reduced pressure. The yield of(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+3)(cyclopentadienyl) (A) was 1.047 g,77.6 percent. ##STR7##

The ESR (Electron Spin Resonance) spectrum of this material exhibitedtwo lines at room temperature centered at g=1.973. The product'sidentity was confirmed by reaction with lead(+2) chloride as in Example2, Preparation B to give (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!(cyclopentadienyl)titanium(+4)chloride.

Preparation B:

0.0987 g (0.248 mmol) of (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!(cyclopentadienyl)titanium(+4)chloride asprepared in Example 2, Preparation A and 0.012 g (0.49 mmol) magnesiumgranules were stirred overnight in 5 ml THF. The originally red-orangesolution turned olive green. The solvent was removed under reducedpressure. The residue was extracted with pentane, the solution wasfiltered and the solvent was removed under reduced pressure. The yieldof the yellow-green product (A) was 0.0825 g, 91.8%.

Preparation C:

1.6744 g (3.26 mmol) of (MgCl.THF)₂ (C₅ Me₄ SiMe₂ NCMe₃) and 0.600 g(3.26 mmol) of cyclopentadienyltitanium(+3) dichloride (preparedaccording to Aust. J. Chem. 1971, 24, 2533-2540) were combined in aflask with 35 ml THF. After stirring overnight, the solvents wereremoved under reduced pressure from the green solution. The residue wasextracted with pentane, filtered and concentrated to give the product(A) as a yellow-green powder. The yield was 0.691 g, 58.4%.

Preparation D:

1.016 g (4.76 mmol, based on the monomer) of (C₅ H₅)₂ TiCl!₂ (preparedas in Inorg. Chem., 1975, 14, 2192) and 2.442 g (4.76 mmol) (MgCl.THF)₂(C₅ Me₄ SiMe₂ NCMe₃) were combined in a flask with 70 ml THF. The greenreaction mixture was stirred overnight. The solvent was removed underreduced pressure, the residue was extracted with toluene and theresulting solution was filtered. Several milliliters of 1,4-dioxane wereadded. The precipitated solids were filtered off and the solvent wasremoved. A small portion (0.156 g) of the green solid was removed andreacted with PbCl₂ as in Example 2, Preparation B to form (B) in 98.2%yield. The remaining green solid was extracted with pentane and thesolution was filtered from a small amount of grey-white powder. Thesolvent was concentrated, the product was recrystallized twice frompentane in the freezer. The total yield of (A) was 1.332 g, 77.2%.

Preparation E:

Powdered (C₅ Me₄ SiMe₂ NCMe₃)(MgCl.THF)₂ (0.5309 g, 1.03 mmol) was addedto a solution of 0.2496 g (1.03 mmol) (C₅ H₅)₃ Ti (prepared according toAust. J. Chem., 1968, 21, 807-810) in 25 mL THF. The deep green solutionimmediately turned a lighter olive green. The reaction mixture wasstirred overnight. The solution was filtered and the solvent was removedunder vacuum. The residue was extracted with toluene, then filtered andthe solvent was removed under vacuum. The residue was extracted withhexane, then filtered and the solvent was removed under vacuum. The palegreen solid was slurried in a small amount of hexane, then filtered offand dried under vacuum. The yield of yellowish green product was 0.3717g, 99.9%. The product was identified as product (A), as follows. A smallamount (about 0.015 g) of the product (A) was oxidized in C₆ D₆ in anNMR tube by shaking with excess PbCl₂ to give (C₅ Me₄ SiMe₂ NCMe₃)TiCl(C₅ H₅) which was identified by its ¹ H and ¹³ C NMR spectra. Noother Cp-containing products were present.

EXAMPLE 2 (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+4)(cyclopentadienyl)chloride

Preparation A:

To a solution of 0.5577 g (1.51 mmol) of (C₅ Me₄ SiMe₂ NCMe₃)TiCl₂(prepared according to EP-A-416,815) in 20 ml THF was slowly added 0.841ml of 1.8M (0.151 mmol) sodium cyclopentadienide in THF. The reactionmixture was heated gently. The color turned deep red within a shorttime. After stirring overnight the solvent was removed under reducedpressure. The very dark red residue was extracted with pentane, thesolution was filtered and the solvent was removed under reducedpressure. The crude product was recrystallized from 2 ml pentane at -40°C. The red product (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+4)(cyclopentadienyl)chloride (B) wasdried under reduced pressure. The yield was 0.5248 g, 87.1%. Thestructure was confirmed by NMR: ¹ H NMR (C₆ D₆) δ5.86 (s, 5H), 2.48 (s,3H), 1.82 (s, 3H), 1.77 (s, 3H), 1.59 (s, 3H), 1.35 (s, 9H), 0.61 (s,3H), 0.25 (s, 3H). ¹³ C NMR (C₆ D₆) δ137.7, 135.5, 129.6, 125.4, 114.3,109.4, 63.7, 34.2, 16.8, 15.1, 12.9, 12.8, 9.7, 6.1. ##STR8##Preparation B:

In a flask were combined 0.700 g (1.93 mmol) of product (A) as preparedin Example 1 and 0.282 g (1.01 mmol) lead(II) chloride with 30 mltoluene. The resulting deep red solution was stirred for three hours,then filtered from metallic lead and the solvent was removed underreduced pressure. The red crystalline product was washed with 2 ml coldpentane, then dried under reduced pressure. The yield of product (B) was0.7455 g, 97%.

Preparation C:

1.500 g (2.92 mmol) of (MgCl.THF)₂ (C₅ Me₄ SiMe₂ NCMe₃) and 0.6411 g(2.92 mmol) of cyclopentadienyl titanium trichloride (prepared accordingto J. Am. Chem. Soc. 1958, 80, 4744) were combined in a flask with 35 mlTHF. After stirring overnight, the solution was filtered and the solventwas removed under reduced pressure. The residue was extracted withpentane, filtered and concentrated until the solid began to form. Afterchilling to -35° C., the solids were collected on a filter, washed twicewith 2 ml cold pentane, then dried under reduced pressure to give theproduct (B) as a red powder. The yield was 0.6369 g, 54.8%.

Preparation D:

1.0185 g (4.09 mmol) of bis(cyclopentadienyl)titanium dichloride(purchased from Aldrich) and 2.099 g (4.09 mmol) (MgCl.THF)₂ (C₅ Me₄SiMe₂ NCMe₃) were combined in a flask with 50 ml THF to form a darkgreen reaction mixture. After stirring overnight, the resulting mixturehad turned brownish red, and the solvent was removed under reducedpressure. The residue was extracted with toluene, then filtered and thesolvent was removed under reduced pressure. The residue was extractedwith pentane and the red solution was filtered from a grey solid. Thesolvent was removed to give an impure brick-red solid. 1 to 2 ml of1,4-dioxane were added to a benzene/toluene solution of the red solid,then the solvent was removed. The residue was extracted with pentane andthe solution was filtered from a small amount of grey powder. Theproduct was recrystallized twice from pentane in the freezer. The yieldof product (B) was 0.5077 g, 31.2%.

Preparation E:

Powdered (C₅ Me₄ SiMe₂ NCMe₃)(MgCl.THF)₂ (0.6358 g, 1.23 mmol) was addedto a solution of 0.2642 g (1.23 mmol) (C₅ H₅)TiCl₂ (OCH₃) (prepared byreaction of (C₅ H₅)TiCh₃ with NaOCH₃) in 30 ml THF. The colorimmediately changed from lemon yellow to deep brownish-red. The reactionmixture was stirred for two days. The solvent was removed under vacuumand the residue was extracted with hexane, then filtered. The solutionwas concentrated and placed in a freezer at -35° C. The product wascollected on a frit and washed with 3×2 ml portions of cold hexane. Theorange powder was dried under vacuum. The product was identified by ¹ HNMR spectroscopy as the title compound with none of the methoxy analoguepresent. The yield was 0.1556 g, 31.8%.

Preparation F:

Powdered (C₅ Me₄ SiMe₂ NCMe₃)(MgCl.THF)₂ (0.6644 g, 1.28 mmol) was addedto a solution of 0.3502 g (1.28 mmol) (C₅ H₅)₂ TiCl(OCH(CH₃)₂)(preparation analogous to the procedure for (C₅ H₅)₂ TiCl(OC₂ H₅) in J.Am. Chem. Soc. 1980, 102, 3009-3014) in 25 ml THF. The bright orangesolution immediately turned deep brownish-red. The reaction mixture wasstirred for two days. The solvent was removed under vacuum and theresidue was extracted with toluene, then filtered and the solvent wasremoved under vacuum. The residue was extracted with hexane, filteredand recrystallized in the freezer. The yield of red-orange product,identified by ¹ H and ¹³ C NMR as (B), was 0.3800 g, 74.3%, with none ofthe isopropoxy analogue being present.

EXAMPLE 3 (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!zirconium(cyclopentadienyl)chloride

To a solution of 0.8286 g (2.01 mmol) (C₅ Me₄ SiMe₂ NCMe₃)ZrCl₂(prepared according to EP-A 416,815) in 60 ml ether was slowly added1.12 ml of 1.8M (2.02 mmol) sodium cyclopentadienide in THF. Thereaction mixture was stirred for several days, then filtered and thesolvent was removed. The colorless solid was slurried in pentane,chilled in a freezer, collected on a filter, washed twice with 2 ml coldpentane, then dried under reduced pressure. The yield of the product (C₅Me₄ SiMe₂ NCMe₃)ZrCl(C₅ H₅) was 0.7270 g, 81.8%. ¹ H NMR (C₆ D₆) δ5.97(s, 5H), 2.36 (s, 3H), 1.85 (s, 3H), 1.81 (s, 3H), 1.67 (s, 3H), 1.29(s, 9H), 0.61 (s, 3H), 0.38 (s, 3H). ¹³ C NMR (C₆ D₆ ) δ132.7, 130.2,126.1, 122.9, 112.9, 106.2, 57.7, 35.2, 15.6, 14.5, 12.3, 12.2, 10.1,6.7.

PART B: Preparation of Complexes of Formula (I)

EXAMPLE 4 (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+3) 2-(N,N-dimethylamino)benzyl

To a solution of 0.2361 g (0.651 mmol) of (A), as prepared in Example 1,in 12 ml of diethyl ether was slowly added 0.0919 g (0.651 mmol) ofpowdered 2-(N,N-dimethylamino)benzyl lithium, prepared by reaction ofbutyl lithium with N,N-dimethyl-o-toluidine, accompanied by stirring. Acolor change was apparent within 1 hour. After 48 hours the solution wasfiltered to remove lithium cyclopentadienide (0.0458 g, 97.6%). Thesolvent was removed under reduced pressure from the dark reddish brownsolution. The yield of red-brown product was 0.2801 g, 99.6 percent.

The product's identity as (N-t-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+3) 2-(N,N-dimethylamino)benzyl (C)was confirmed by its reaction with lead(+2) chloride. A solution of (C)in C₆ D₆ was placed in an NMR tube. Excess lead(II) chloride was addedand the sample was shaken. The red-brown solution turnedyellow-orange-brown. The excess lead(+2) chloride and lead metal whichformed were tipped away from the solution. The ¹ H NMR showed theproduct to be (N-t-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+4) 2-(N,N-dimethylamino)benzylchloride by comparison with an authentic sample which was prepared byreaction of (C₅ Me₄ SiMe₂ NCMe₃)TiCl₂ with 2-(N,N-dimethylamino)benzyllithium as described in WO 93/19104. ¹ H NMR (C₆ D₆) 7.00 (m, 1H), 6.92(m, 1H), 6.78 (m, 2H), 2.77 (s, 1H), 2.73 (s, 1H), 2.52 (s, 6H), 2.27(s, 3H), 2.03 (s, 3 H), 1.90 (s, 3H), 1.57 (s, 9H), 1.01 (s, 3H), 0.57(s, 3H), 0.50 (s, 3H).

EXAMPLE 5 (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+4) bis(2-(N,N-dimethylamino)benzyl)

To a -35° C. solution of 0.2134 g (0.536 mmol) of product (B), asprepared in Example 2, in 25 ml diethyl ether was slowly added 0.0757 g(0.536 mmol) of powdered 2-(N,N-dimethylamino)benzyl lithium accompaniedby stirring. After allowing to warm to room temperature and stirringovernight, the color of the solution was reddish orange. ¹ H NMRanalysis of this intermediate product shows the absence of both thestarting material and the chloro complex (C₅ Me₄ SiMe₂ NCMe₃)Ti(CH₂ C₆H₄ (o-NMe₂))Cl (by comparison with an authentic sample prepared byreaction of (C₅ Me₄ SiMe₂ NCMe₃)TiCl₂ with LiCH₂ C₆ H₄ (o-NMe₂)). The ¹H NMR spectrum of the compound is consistent with a structurecorresponding to (C₅ Me₄ SiMe₂ NCMe₃ )Ti(CH₂ C₆ H₄ (o-NMe₂))Cp. A secondequivalent of the lithium reagent was added (total 0.1514 g, 1.072 mmol)to the reaction mixture. The reaction mixture was stirred overnight,then the solvent was removed under reduced pressure from the darkreddish brown solution. The residue was extracted with pentane, thesolution was filtered and the solvent was removed. The yield of thered-brown product (D) was 0.2778 g, 91.6%. ¹ H NMR (C₆ D₆) (C₅ Me₄ SiMe₂NCMe₃)Ti(CH₂ C₆ H₄ (o-NMe₂))Cp: δ7.22 (m, 1H), 7.08 (m, 2H), 7.07 (m,1H), 5.78 (s, 5H), 2.58 (s, 6H), 2.4 (br, 2H), 2.15 (s, 3H), 1.82, (s,3H), 1.62 (s, 3H), 1.46, (s, 3H), 1.35 (s, 9H), 0.71 (s, 3H), 0.67, (s,3H); (C₅ Me₄ SiMe₂ NCMe₃)Ti(CH₂ C₆ H₄ (o-NMe₂))₂ : ¹ H NMR (C₆ D₆) δ7.1(br, 2H), 6.95 (br, 6H), 2.70 (d, 2H, J=9.34 Hz), 2.49 (br s withshoulders, 14H), 1.87 (s, 6H), 1.85 (s, 6H), 1.50 (s, 9H), 0.51 (s, 6H).¹³ C NMR 149.1, 145.7, 133.7, 131.4, 129.4, 123.5, 123.2, 119.3, 100.5,80.1, 60.0, 44.7, 34.1, 14.9, 11.6, 6.6.

EXAMPLE 6 (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+4) dimethyl

To a -35° C. solution of 0.2099 g (0.527 mmol) of product (B), asprepared in Example 2, in 25 ml diethyl ether was slowly added 0.595 mlof 1.012M (0.602 mmol) methyl lithium in solution in ether. The reactionmixture was allowed to warm to room temperature during which time thecolor changed from red-orange to greenish-yellow. After stirringovernight, the reaction mixture was shown by ¹ H NMR to consist of a 6:1ratio of the bis(cyclopentadienyl)monomethyl derivative and themonocyclopentadienyl dimethyl derivative. The remainder of the secondequivalent of methyl lithium was added (total 1.04 ml, 1.052 mmol) tothe reaction mixture and the reaction mixture was stirred overnight. Thesolvent was removed under reduced pressure, the residue was extractedwith pentane, and the solution was filtered. The solvent wasconcentrated until crystals began to form, and then was chilled in thefreezer. The supernatant was decanted and the solid was dried undervacuum to give 0.1611 g, 93.3% of light yellow product which wasidentified by ¹ H NMR spectroscopy to be(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!titanium(+4) dimethyl (Product E). ¹ H NMR (C₆D₆) (C₅ Me₄ SiMe₂ NCMe₃)Ti(C₅ H₅)Me: δ5.66 (s, 5H), 2.22 (s, 3H), 1.82(s, 3H), 1.56 (s, 3H), 1.42 (s, 3H), 1.26 (s, 9H), 0.58 (s, 3H), 0.46(s, 3H), 0.19 (s, 3H); (C₅ Me₄ SiMe₂ NCMe₃)TiMe₂ : δ1.97 (s, 6H), 1.86(s, 6H), 1.57 (s, 9H), 0.51 (s, 6H), 0.43 (s, 6H).

PART C: Polymerization Using Complex of Formula (II)

EXAMPLE 7

A thermostat-controlled continuously-stirred 2 l reactor charged with740 g Isopar E™ (available from Exxon Chemical) and 118 g 1-octene waspressurized with 25 psi hydrogen and 450 psi ethylene and heated to 120°C. 10.0 μmol (N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!(cyclopentadienyl)zirconium chloride (preparedaccording to Example 3) were combined with 5000 μmol (based on the AlCH₃O empirical formula) MMAO (triisobutylaluminum-modifiedmethylaluminoxane) and then added to the reactor. An exotherm of 35° C.was observed. After a reaction time of 15 minutes, the polymer solutionwas removed from the reactor and the solvent was removed. The yield ofpolymer was 138.8 g.

EXAMPLE 8

Example 7 was repeated, except that 2 μmol zirconium complex and 1000μmol MMAO were used. An exotherm of 8.2° C. was observed. The polymeryield was 89.4 g.

EXAMPLE 9

Example 8 was repeated, except that the reaction temperature was 140° C.and 650 g Isopar E and 208 g 1-octene were used. An exotherm of 4.7° C.was observed. The polymer yield was 53.4 g.

EXAMPLE 10

Example 7 was repeated, except that 10.0 μmol(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!(cyclopentadienyl)titanium chloride (B) wereused instead of the zirconium complex. An exotherm of 0.8° C. wasobserved. The polymer yield was 2.0 g.

EXAMPLE 11

Example 10 was repeated twice, except that 10.0 μmol(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane!(cyclopentadienyl)titanium (A) were usedinstead of (B). Exotherms of 0.8° C. and 0.6° C. were observed in eachcase. The polymer yield in each case was 6.6 g.

What is claimed is:
 1. A process for the preparation of amonocyclopentadienyl metal complex corresponding to the formula:##STR9## wherein: Cp* is a cyclopentadienyl group or a substitutedderivative of said cyclopentadienyl group wherein the substituent ishydrocarbyl, silyl, amino, aminohydrocarbyl, halo, halohydrocarbyl,silylhydrocarbyl, hydrocarbylmetalloid or halohydrocarbylmetalloid, oradjacent substituents on Cp* may be linked together, said Cp* beingcovalently bonded to Z and π-bonded to M and containing up to 50nonhydrogen atoms;Z is a divalent moiety comprising oxygen, nitrogen,phosphorous, boron, or a member of Group 14 of the Periodic Table of theElements, said moiety having up to 30 nonhydrogen atoms and beingcovalently bonded to Y and Cp*; Y is a linking group comprisingnitrogen, phosphorus, oxygen or sulfur covalently bonded to M and Zthrough said nitrogen, phosphorus, oxygen or sulfur atom; M is a metalof Group 4 of the Periodic Table of the Elements in an oxidation stateof +3 or +4; R independently each occurrence is a hydrocarbyl group,optionally substituted with one or more amino, phosphino, ether,thioether, or silyl groups, said R having up to 50 nonhydrogen atoms,provided that R is not a cyclopentadienyl group or substitutedcyclopentadienyl group; Q independently each occurrence is hydride, or amonovalent anionic ligand selected from the group consisting ofhydrocarbyl, silyl, amido and phosphido groups, said groups optionallybeing further substituted with one or more amino, phosphino, ether,ester, thioether, or silyl groups, said Q having up to 50 nonhydrogenatoms, provided that Q is not a cyclopentadienyl or substitutedcyclopentadienyl group; and m is 1 or 2; n is 0 or 1; and the sum of mand n is two less than the oxidation state of M; the process comprisingcontacting in an aprotic solvent: 1) a bis(cyclopentadienyl) Group 4metal complex corresponding to the formula: ##STR10## wherein: Cpindependently is a cyclopentadienyl group or a substituted derivative ofsaid cyclopentadienyl group wherein the substituent is hydrocarbyl,silyl, halo, amino, aminohydrocarbyl, halohydrocarbyl, silylhydrocarbyl,hydrocarbylmetalloid or halohydrocarbylmetalloid, or adjacentsubstituents on Cp may be linked together, said Cp being π-bonded to M,and containing up to 50 nonhydrogen atoms;X independently eachoccurrence is halo, hydrocarbyloxy, siloxy, carboxy, sulfido orsulfonato; Cp*, Z, Y, M, Q, and n are as previously defined; and t is 0or 1; and the sum of n and t is three less than the oxidation state ofM; and 2) an alkali metal derivative or alkaline earth metal derivativeof R, wherein R is as previously defined, to form themonocyclopentadienyl complex of formula (I).
 2. A process according toclaim 1 wherein a monocyclopentadienyl complex corresponding to theformula: ##STR11## wherein: R' each occurrence is independently selectedfrom the group consisting of hydrogen, silyl, hydrocarbyl, andsilyl-substituted hydrocarbyl having up to 10 carbon or silicon atoms,or two such R' groups together are a C₃ or C₄ hydrocarbylene moietyforming a fused ring with adjacent carbons of the cyclopentadienylgroup;E independently each occurrence is silicon or carbon; Q is allyl,alkyl-substituted allyl, pentadienyl, alkyl-substituted pentadienyl,alkyl, aryl, aralkyl, silyl, trialkylsilylalkyl, or dialkylaminoaralkylgroup, said group having up to 10 carbons; R is allyl, alkyl-substitutedallyl, pentadienyl, alkyl-substituted pentadienyl, alkyl, aryl, aralkyl,silyl, trialkylsilylalkyl, or dialkylaminoaralkyl group, said grouphaving up to 10 carbons; and a is 1 or 2; m is 1 or 2; n is 0 or 1; andthe sum of m and n is two less than the oxidation state of titanium; isprepared by contacting: 1) a bis(cyclopentadienyl) Group 4 metal complexcorresponding to the formula: ##STR12## wherein: R', E, Q, n, and a areas defined for formula (Ia);t is 0 or 1; X and Cp are as defined inclaim 1; and the sum of n and t is three less than the oxidation stateof titanium; and 2) the alkali metal or alkaline earth metal derivativeof R.
 3. A process according to claim 1 wherein in formula (I) m is 1 or2 and n is 0, and in formula (II) n is 0 and t is 0 or
 1. 4. A processaccording to claim 3 wherein in formula (I) m is 1 and n is 0, and informula (II) n is 0 and t is
 0. 5. A process according to claim 4wherein R is an allyl or alkyl-substituted allyl π-bonded to M,pentadienyl or alkyl-substituted pentadienyl π-bonded to M, ordialkylaminoaralkyl group.
 6. A process according to claim 1 wherein Cpin the bis(cyclopentadienyl) Group 4 metal complex is cyclopentadienyl.7. A process according to claim 1 wherein the aprotic solvent isselected from the group consisting of ethers, aliphatic, cycloaliphatic,aromatic and alkyl-aromatic hydrocarbons.
 8. A process according toclaim 1 conducted at a temperature from -78° C. to 150° C.
 9. A processaccording to claim 1 wherein the bis(cyclopentadienyl) Group 4 metalcomplex corresponding to the formula (II) is prepared by contacting inan aprotic organic solvent: i) a compound corresponding to one of theformulas (Cp₃)MQ_(n) X_(t), (Cp)₂ MQ_(n) X_(t+1), or CpMQ_(n) X_(t+2) ora neutral Lewis base coordinated adduct thereof wherein: n is 0 or 1, tis 0 or 1, and the sum of n and t is three less than the oxidation stateof M; X, M, Cp and Q are as defined in claim 1; and ii) a dianionic saltcompound corresponding to the formula:(L^(+x))_(y) (Cp*-Z-Y)⁻² or((LX')^(+x))_(y) (Cp*-Z-Y)⁻² wherein L is a metal of Group 1 or 2 of thePeriodic Table of the Elements; X' independently is chloro, bromo, oriodo; x is 1 or 2, y is 1 or 2, and the product of x and y equals 2; andCp*, Z, and Y are as defined in claim
 1. 10. A process according toclaim 9 wherein n is 0 and t is 0 or
 1. 11. A process according to claim10 wherein t is
 0. 12. A process according to claim 9 conducted at atemperature of from -78° C. to 150° C.
 13. A process according to claim9 wherein the aprotic organic solvent is selected from the groupconsisting of ethers, aliphatic, cycloaliphatic, aromatic andalkyl-aromatic hydrocarbons.